


Making Up Lost Time.

by TREE3



Category: Undertale (Video Game)
Genre: Gen, Post-Undertale Pacifist Route
Language: English
Status: In-Progress
Published: 2017-01-17
Updated: 2017-01-18
Packaged: 2018-09-18 03:42:42
Rating: Not Rated
Warnings: No Archive Warnings Apply
Chapters: 4
Words: 7,169
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9366512
Author URL: https://archiveofourown.org/users/TREE3/pseuds/TREE3
Summary: To Doctor Alphys, the prospect of entertaining an unexpected guest is unwelcome at the best of times, but when the guest in question has no body, poor communication skills, and a habit of tearing down the laws of physics like a deck of cards, she knows who to call for help. After all, the signs all point to one thing...Mostly.As events unfold and ever increasing numbers of buried hatchets are unearthed, however, Alphys quickly finds her worst fears being realized- namely, that she will have to be sole mediator in a truly awkward situation. Also, lives might be at stake.All said, it's a good thing she has the role model of a small, melancholy child to guide her.





	1. Anomaly

**Author's Note:**

> Given a choice between 'possible' and 'pseudoheadcanonically feasible', the deciding factor is usually whether or not you can get Sans to say "bad time".

It started, as do so many things, with the blink of a screen. The screen in question was one of many dotted across the lower levels of the Hotland labs, mounted like the world's least inspired art showcase on the planes of indeterminate green-grey matter that served for walls there. None of the human research teams that had tramped through since the fall of the barrier had bothered to redecorate. None of them, in fact, had even bothered to stay the night after realizing with growing horror that even Dr. Alphys’ most desperate and introductory attempts at explaining the field of “Arcano-Electric Quantum Engineering” would require rewriting most of the current laws of physics, contradicting every major human belief system, and allowing for seventeen overlapping spatial dimensions. Worse yet, despite her mind-expanding knowledge of scientific theory beyond human comprehension, she… just seemed to be the maintenance person. So, it came to pass rather quickly that the Core (a resource too valuable to abandon even long after the Underground had been deserted) was left in the theoretically capable, clawed hands of literally the only person in the world who knew how to make it work. Alphys really couldn’t complain, considering the week-long shifts alone Underground allowed for plenty of, er… recreation. Her “historical archives” had been expanded to the point of mythological status among even human aficionados, and despite the temporary absence of Undyne’s balancing presence, the otaku lifestyle still held a comfortingly nostalgic appeal in small doses.

Right now, though, she was looking at a different sort of screen. This monitor, when not occupied with the task of dispensing unnecessarily fragmented exposition, usually displayed a graphic of the cosmic background radiation of the universe. Fairly standard-issue as far as lab paraphernalia went, but the part that was causing beads of perspiration to roll down the observer's yellow, scaled brow was the fact that, by definition, cosmic background radiation isn't really supposed to  _ change _ . 

The rebellious pricks of static begged to differ. That one cluster was actually starting to look kind of like a... oh. Oh no.

Alphys nearly dropped her phone trying to turn it on- her hands were getting slicker by the second, in flagrant disregard to any human model of reptilian biology. There really was only one person to call in this scenario, but…

Her claw hesitated above the dial pad. Would he want to know?

A moment more like this, then a sudden memory of shuffling whiteness, distorted laughter, sticky refrigerators. Alphys shuddered, and was filled with a sort of determination.

She dialed the first digit.

She thought of Undyne suplexing a boulder.

She dialed the second digit. 

She thought of Frisk defying death, again and again, to free everyone from the darkness of Ebott.

She dialed the third digit.

She remembered that Mew Mew Kissy Cutie 3 was due to premier next month.

She dialed the rest of the number. Two-and-a-half rings later, the phone was picked up by an old acquaintance.

"heya alphys. long time no see. you, uh, find something neat down in the core?"

"Uh, erm, y-yeah... I guess I did..." she replied in the usual terrified stammer. Sans was left to break the following silence.

"so... are ya gonna tell me what it is? my bro got it in his head that he and frisk should start a basketball team, so i'm kinda busy coaching. and, uh, reinflating basketballs."

There was a distant, yet highly audible exclamation of "PREPARE TO 'GET DUNKED ON', HUMAN!" Sans chuckled a little more than necessary.

"Oh, yeah, that's, uh, g-great!" said Alphys. "It's just, see, there's k-kinda an anomaly in the... well, the sensors are showing a... uh... it almost sorta looks like a…"

The elevator dinged behind her. Sans stepped out.

"heheh. that sure is 'cool'. mind if i have a peek?"

Alphys, whose phone was now beeping forlornly from it's newly formed hole in the ceiling, opened her mouth, then shut it again. In her time knowing Sans, she had learned to expect a lot more questions than answers. There was, however, a manic note to his infallibly casual greeting that worried her. She lifted a shaking finger toward the monitor. Sans shuffled up to it with all the stoic nonchalance plumber going to fix a leaky toilet.

"hmm, cosmic background map, eh? an immutable, universal signature from the very dawn of creation. very sciencey. guess asgore likes to know what he's paying for, huh?." He leaned a bit closer. "and whaddya know, you're right. someone's put  _ hands _ on it. heh."

His grin audibly stiffened. There amid the background signature, two blobs of static had coalesced to form two crude, five-fingered forms. The first pointing down, all but the index finger curled; the second open, fingers splayed upwards.

"H I", Sans read. Then he sighed. "oh brother..."  
  


 

*  *  * 

 

A skeleton and a lizard sat to tea…

  
  


The “tea” in this case was actually a bottle of mayonnaise and a glass of unsettling pink fluid that Alphys, when asked, claimed was made from seaweed. Sans, in turn, deflected her questioning gaze by insisting that this was no time for “ketch-up”. They had a job to do, and they’d need all their wits about them. Because, of course, this was about G-

“What was his name again?”

Sans pinched the bridge of his nasal cavity.

“gaster, alphys. you know- ex royal scientist, mad genius, your old boss… my  _ brother _ . this is about gaster.”

“Right! S-sorry!”

Alphys knew who Gaster was, of course. Everyone knew the… old royal scientist. He designed the Core, which powered the entire underground. Well, at least, if he didn’t… then who did? So he must be pretty much famous. He… whoever he was.

Alphys shook her head in frustration. What was it about that name- that  _ man _ \- that just kept slipping from her mind?

Sans took a deep breath. “hey, don’t worry about it. he’s just not exactly the most memorable guy.”

This was, as far as Alphys could glean, a lie, considering the ‘guy’ in question was a seven-foot skeleton with a penchant for dressing like the Grim Reaper and more idiosyncrasies than a bag of Temmies. 

“Yeah… I guess not” Alphys muttered. “But, what actually happ-”

“luckily for us,” Sans cut in, “all that matters for now is that he needs our help. unless you can think of any other brilliant scientists who never quite grew out of finger painting, there’s, uh,  literally no one else it could be. even you remembered his handwriting somehow.”

Alphys shifted nervously. “Well, where do we start? All we have to go on are two clusters of thermal imbalance strewn across the entirety of cosmic space. It’s n-not really… physically possible.”

“can’t argue that chain of logic,” Sans chirped back, “so how ‘bout we stop following it? my bro is an interesting guy. he never really bothered with the laws of physics unless he thought of an interesting way to break one of them, so it might be a good idea to think outside the box.” He drummed four fingers against the top of his skull. “well, i dunno about you, but when someone says “hi” to me, i usually send it right back at ‘em. how’s about we work out a way to talk to the old guy first?”

“Across a… t-trans dimensional chronosynclastic anomaly from the creation of the universe?”

“couldn’t’ve said it better myself.”

“Well, I d-don’t really think it’s possible, but I g-guess with the Core’s full power available and the shipment of superfluid helium that just c-came in we could rig up some sort of… huh? Ohmygod Sans!”

Following Alphys’s frantic gesture to the monitor behind them, Sans saw the cause for concern. The original two clusters of static were gone, and replaced by no fewer than nineteen new, impossible doodles on the dawn of time. Not just hands now, but skulls, suns, stars, crosses….

Sans’s bony brow creased for a moment, before he burst into laughter.

“I C A N H E A R Y O U J U S T F I N E”, he read. “welp, I guess that solves our problem.”

He got to his feet, grin wider than ever, and removed a hand from his pocket to place against the screen.

“heheheh...wow. it’s been a  _ long  _ time, bro. oh god… what am i gonna tell pap?”

He couldn’t seem to keep from chucking. Alphys was still seated, unsure of how to react. She, too, found herself smiling at the bizarre reunion, but this was offset by a sizeable helping of existential dread. Sans had found his long lost brother, but… how lost did you need to get before your only avenue of reconnection was scrawling messages across intergalactic space? More importantly… how could you come back?

“look, i haven’t got a clue how you’re messing with space and time like that, but to be perfectly honest, i don’t really care. somehow, you’ve found a way to make contact, and if you could get that far on your own, there’s no way the three of us can’t find a way to get you out of this mess.”

He gingerly replaced his hand into his hoodie, before continuing, slowly.

“we made it to the surface, y’know, doc? the king and queen, me, pap, alphys... everyone, somehow. if i’m being honest, i didn’t think it was possible any more...even after the kid showed up. but you probably know everything already, huh?”

The screen remained ominously still.

“hey, doc, this thing still on?” 

About ten seconds of breathless, uncomfortable silence. Then, the screen began to change once more. The arcane symbols faded, but none appeared to replace them. Instead, a string of quite normal text. Seven letters. Courier New font, to Sans’ eye. 

It read: “ `I’m sorry` ”.

Sans stood perfectly still. Alphys, still unsure of exactly how to react, or what she was even reacting to, felt like an eavesdropper on a conversation she probably had no place overhearing. She opted to follow Sans’ lead and wait for the screen to scroll. It did.

“ `I had to get your attention. It was a stupid idea.` ”

Sans stared up into the monitor, motionless.

“is this some kinda joke?”

Alphys wasn’t sure who had spoken at first. The sound was simply… menacing.

Again the tense silence stretched unbearably long. It was a case of who would speak first.

Finally, and somehow wretchedly, the monitor faded in one more line: “ `I’m not Gaster.``` ”

Sans exploded. “you think i haven’t gathered that?!”

His shout reverberated down every hallway of the lab. Alphys took a sudden and passionate interest in her beverage. The skeleton fumed on.

“do you think i’m  _ confused  _ about what’s going on here? i know  _ exactly  _ what you are. and y’know what? i honestly believed you were gone from this world. that this would be the  _ last time _ .”

Sans’s voice was hoarsening slightly, but he caught it with a hearty laugh.

“jokes on me, though. turns out you were my  _ brother _ all along!”

Sans turned his back to the monitor, and Alphys saw that his eyes had faded to dead black as he strode back over to the table and reclaimed his seat.

“anyone ever tell you you’ve got a sick sense of humour?” he whispered, before slumping on the table, skull in hands.

 

Alphys began to sweat again. Sans… wasn't supposed to act like this. She would never claim to know the skeleton well- although maybe nobody would- but anyone who’d ever had a conversation with him caught the gist of his shtick pretty quickly: He knew more than he was letting on, he felt differently than his face betrayed, and he’d be  _ damned _ if he couldn't make a discussion about the moral justifiability of child-murder sound as nonplussedly flippant as an invitation to brunch. Yet his outburst upon reading the screen’s last announcement was undeniably the most ‘plussed’ thing Alphys had heard that day outside of the anime she’d been watching prior to his arrival. It was like seeing Frisk kick a puppy, or Papyrus win a hand of poker.

 

“I’m… I’m really sorry Sans.” she managed to choke out. 

“alphys.” Sans looked up to meet her eyes. “don’t.  _ ever _ . apologize for that thing again. but... thanks anyway.”

She drummed her claws against the linoleum. Eventually,  Sans’s brow furrowed.

“wow. you, uh… probably don’t know what even going on, do ya?”

“Nope.” She answered with more confidence than anything else she’d said that day.

Sans sighed again. “oh jeez. um... wanna go to grillby’s?”

“Where?”

“oh. never been to snowdin, huh? just picture the mtt restaurant, except with food. come on, it’ll be fun.”

Alphys glanced nervously at the still-fizzing screen over Sans’ shoulder.

“B-but, what ab-bout  _ them _ ?”

“hah!" the skeleton laughed. "don’t sweat it. they’ve got all the time in the world. besides, we won’t be gone long. i know a shortcut.”


	2. Playing Ketchup

It was a fast shortcut, and Sans realized his mistake almost as quickly once he felt the chill start to creep into his bones. Where he had expected the smell of good food and the sound of bad laughs, he was met with silence and the scent of hardwood. The warm, flickering glow that used to shine from Grillby’s match-head was gone, and replaced with a cold grey light lancing in from the snow-caked windows behind them. There wasn’t even a fireplace to kindle. He smacked his palm into his face with a clack.

“aw, come on sansy, get it together!” he moaned to himself. “barrier’s broken. grillby’s probably up there selling cocktails to human high-rollers… what was i thinking bringing us back to this old dive, huh?"

The last bit was more or less directed at Alphys, who was leaning against a wall behind him and breathing heavily after having just teleported several kilometres.

“eh, never mind.” he muttered agitatedly. “let’s just grab another shortcut back to the lab and i can get this all sorted out…”

The room suddenly spun 180 as Alphys grabbed his shoulder and pivoted him to face her.

“Sans, we just teleported! _Teleported_! Can you please tell me what’s going on?”

The genuine terror in her voice was enough to give him pause. He jammed his hands back into his pockets, shoulders sagging slightly, and took a long breath.

“o-kay... maybe what happened in the lab just now shook me up a… little more than i thought it would. maybe i’m not thinking totally straight. that’s fine. totally cool. let’s just take five and…”

He groped behind the counter and produced an abandoned red bottle.

“...ketchup.”

Alphys appeared unamused, even when he wiggled the bottle slightly.

“alright, i can take a hint.” He patted a stool at the bar. “here. have a seat.”

 

The two of them hoisted themselves up onto the unfortunately tall bar stools, with varying degrees of elegance. As Alphys struggled not to topple over, Sans cracked his knuckles loudly and cleared what passed for his throat. When she was settled, he lurched slowly into exposition.

“i’m kinda used to not bringing this up, so, uh… let’s just get to the point. basically, what if i told you that frisk wasn’t the only one who fell into the underground that day?”

“I would, erm… ask who else fell?”

A moment passed.

“Oh. And be surprised.”

“thank you. as for who it was, though, i never knew exactly. until now.”

With an outstretched finger, he sketched a rectangle in the frost clinging to the bartop. Inside, a waving hand.

“back when i was working with the doctor, our reports showed a massive anomaly in the time-space continuum. timelines jumping left and right, stopping and starting… until suddenly, everything ends. a total reset, back to a common date. nobody else even noticed, because nobody could remember past it.”

Alphys’ eyes widened behind her glasses.

“Determination...” she murmured, almost inaudibly. Her features slowly set into a rictus of horror. “When d-did it… stop?”

Sans gave a helpless shrug.

“it hasn’t.

The words quickly faded in the room’s frosty stillness, and when no reply ever came to fill the void Sans glanced over his shoulder to see Alphys petrified, staring into the bar with rapidly moistening eyes. Sans scratched his parietal bone.

“and yeah. at first, it was the flower. i could say a whole lot about that flower, but instead, i’ll just say one thing that i know for sure: it isn’t your fault.”

Alphys said nothing.

“welp, make of that what you will, but this story ain’t finished yet. remember, i said _at first_ it was the flower. the point i’m making is more that it’s not him any more. on the day frisk first fell, he was displaced. usurped, i guess. bottom line, something with even greater determination had entered this world, and my first thought was that it was frisk. as you can maybe guess, the start of our relationship was, er, strained, but then, well… they turned out to be _frisk_. plus, even if i was right, it’s not like just going and killing ‘em would have made a huge difference.”

Seeming to snap to her senses, Alphys turned to him in shock.

“You c- _considered_ that?”

“once or twice. but even back then, i’d always suspected more was at work than one pipsqueak and their will to live. there was something else lurking behind the scenes. something with an unnatural level of determination. i was just guessing at that point to be honest, but seeing as they’ve literally just dropped by to give that theory a personal thumbs-up, i think it’s safe to finally give ‘em that name i always thought was so catchy: the anomaly.”

Suddenly, Alphys slammed a fist onto the bartop hard enough to make the windows rattle. Sans actually jumped slightly.

“Sans. Please. Stop talking.”

Sans stopped talking.

“Y-you… spent _years_ … trapped in a loop of time. Because of me. And you’re just… g-going on about science like n-none of that even matters!”

Sans’ eye sockets narrowed.

“i said it once, alphys, it wasn’t your fault.”

“I don’t _care..._ whose fault you think it was! You w-were the only one who knew. You never even told anyone!”

“yeah, well i hope now you can see why."

 

Alphys froze again, breathing heavily and beginning to shiver in the icy air.

“I just… there’re so many stupid, _cowardly_ things I did back then. I spent all that time hiding away while other people were being hurt by my mistakes, a-and every time it seems like I make something right, I find out that things were even w-worse than I’d thought. But nobody ever seems to hold anything against me! It's… not fair! I’m so sorry Sans. For everything.”

Sans stared intensely over the bar for a long moment, as if studying wood grain in Grillby’s empty liquor cabinet . He did not crack a joke. Finally, slowly, he turned to meet Alphys’ eyes, and held out a phalangeal hand.

“thanks, alph. apology accepted, for what it’s worth.”

They shared a bony, clammy, awkward handshake. After a little while, Sans spoke up a touch uncomfortably.

“i know we’ve both maybe got times in our lives we’d rather not remember. but the important thing to keep in mind now is that the past, finally, is _behind_ us.”

He chucked ever so slightly at that. For some reason, Alphys did too.

“It’s, uh… actually really hard to keep that straight sometimes. y’know… that we can all actually move forward now. live our lives. maybe make some choices that actually matter…”

He appeared to notice something on the bar in front of him, and began wiping away the frost with his hoodie sleeve.

“it’s... kinda terrifying.”

Alphas sniffed.

“Yeah. Time warp or not, I think I know what you mean.”

She looked over to where Sans was polishing the bartop. Beneath the frost was a long message in many different hands, scrawled on the wood in permanent marker. Squinting through her glasses, she could just make out the words:

 

**Last Day Underground, 20--. The only way’s up from here.**

 

The date had been smudged out. Underneath sprawled a leger of dozens of signatures of all descriptions. Some legible, some barely more than scribbles, and a few that were just inky paw prints. At the bottom of the list, in a rotund, looping print, was simply: “sans”.

A thought flitted across his face.

“hey, alphys, um… good talk. very healing. it’s just that, if you remember the ‘science’ i was rambling on about a minute ago… well, the anomaly still exists, right?”

Alphys paused half-way through the action of wiping her eyes and smiled a smile of pure cosmic dread. She giggled weakly.

“Heheh… oh yeah. _That_.”

Sans smiled the same smile as always. If anyone knew exactly what emotion it was supposed to express, they were afraid to say so.

“yeah. so, whaddya say you and me go _deal with_ that problem? literally. just for the sake of preserving all that great character development.”

Alphys nodded like a jackhammer.

“i knew i could count on you”

 

With a crunch that suggested a tree being uprooted somewhere nearby, Sans cracked every knuckle on both of his hands, and continued with his shoulders, back, neck, elbows and, somehow, his pelvis. His grin spread wider by the second.

“man that feels weird. i gotta watch out- nine doctors outa’ ten say determination’s bad for monsters... but maybe it’s about time i got off the wagon. you ready for a shortcut?”

The two of them grasped hands once more, until the universe blinked and they were gone.

 

The jukebox in the corner, which had simply been overheated all along, sparked slightly as the shortcut’s spacetime ripples passed through it, and shuddered into life. A single vinyl disk began to revolve deep in it’s wooden heart, and from its dusty speakers lept an achingly beautiful orchestral rendition of Jerry’s theme song. It played on loop until the needle snapped, and was never heard by a living soul.


	3. Apology

From hollow light to darkness, screens still leering from the walls. The one controlled by the anomaly had faded back to cosmic static in their absence, leaving no trace of its presence. It wouldn’t have been hard to forget anything had happened at all… if that was what either of the pair had in mind.

As it was, they both stared the screen down as though confronting a dragon, or a human child. Alphys elbowed Sans.

“M-maybe you should, er, go first. You’re better at… this kinda stuff.”

“what kinda ‘stuff’?”

“Y’know… er… arbiting.”

“wonder where i picked up that talent...”

 

He shuffled up to the monitor, placed his hands carefully in his pockets, tilted his head upwards, and addressed the static with a level tone.

“heya. hope ya don’t mind the interruption. we’ve been, uh, busy. so, if it’s not too much trouble on your end… mind explaining exactly who, what, where, and  _ why  _ you actually are?

The static fizzed unperturbed.

“uh, look, i’m starting to feel self-conscious talking into an lcd screen full of nothing. if you wanted to tell us something so badly, go ahead and spit it out before someone loses their patience.”

The screen suddenly shifted.

“ `You still want to talk to me?` ”

Sans chuckled icily.

“pretty funny way to phrase that question! i think i know what you were getting at though, so i’ll just go with  _ yes _ .”

The static shifted more quickly now.

“ `I realize what you must think of me, you know. I know that you don’t trust me` .”

Sans just nodded.

“ `But, I promise I was only ever trying to help.` ”

“does tying our timeline into a noose count as ‘help’?”

“ `I never realized what I was doing.` ”

“did you ever try to find out? did you ever  _ care _ ?

Sans’ tone has gone from chilly to pure venom.

“do you realize that, this very second, you could destroy all of our lives, and there’s  _ nothing we can do about it _ ? i just want to make sure we're on the same page here.”

 

“ `YES` ”

 

Sans and Alphys’ breath echoed through the dimness as the next line faded into visibility.

“ `I know. And I’m sorry. So sorry… for everything. I don’t even know what I am. Not here. I don’t know why I have this power. I didn’t-` ”

The rest of the text scrolled off the screen. Alphys eventually tapped Sans on the shoulder.

“Sans… I don’t think this thing is m-malicious. I know you’re upset, b-but, maybe being angry with it will make things worse.”

“alphys, you said i was better at this kind of thing, yeah? let me handle it.”

He turned back to the anomaly.

“before you go and get all sappy, i want to know. how many times?  how many times did you reset all of this?”

The anomaly took some time to respond. 

“ `I don’t remember. I tried to keep Frisk safe, but they died a few times. Especially from Asgore. Don’t tell him I said that.` ”

“guess that explains the anomaly in the spacetime… wait, what?”

Sans was taken aback.

“what do you mean, frisk died? i asked you how many times you  _ reset _ .”

“ `I thought that was what you meant… when Frisk came back from the dead by rewinding time.` ”

“well, that’s… no, i don’t  _ blame  _ the kid for not wanting to die. i just… how can you not know about  _ resetting _ ? you should be able to pull it off without even breaking a sweat. your determination is freakish.”

“ `I’ve never wanted to. I didn’t even know I could. Why would I do that?` ”

 

As Sans was drawing in air for a response, he found his ribcage suddenly compressed by a pair of stubby, yellow arms. 

“Bee-are-bee!” Alphys grinned manically at the anomaly, before dragging the skeleton bodily from the room. Once they were safely around a corner and the illusion of privacy had reinstated itself, she whirled to face Sans with an insane glint in her eyes.

“Sans! This is not going well! I don’t think this guy’s even who you’re angry at!”

“who should i be angry at, then? the flower? frisk?  _ you _ ?”

Alphys winced, but kept her eyes locked with the skeleton.

“Yes! Maybe!… I don’t know! You seem pretty convinced that we’re dealing with the fate of the world here, and if that's true we can’t afford to be angry if it won’t help. We can’t make this personal!”

Sans gave a brief, frustrated sigh.

“alphys... i’m sorry i just said that, okay? maybe this isn’t anyone’s fault.  _ maybe _ . but this is still the anomaly we’re talking about. malicious or not,  _ ignorant  _ or not, this isn’t just a case of forgive and forget. nobody is safe as long as they exist. i just didn’t realize they were only ever keeping the kid alive.”

“I know. Just… try to be reasonable. Give it a chance. And…  _ especially _ … don’t go filling it in on any more world-ending powers it controls!”

“heh, yeah... sounds cool. now please, let’s not give it time to think too hard.”

 

They sidled back into the anomalous room, where Sans spread his arms toward the monitor in a gesture of theatrical amicability.

“okay, water break over, much obliged. it’s getting hot in here, eh? so... assuming your story is legit… what did you want to tell us so badly in the first place? if it’s a  _ really  _ good reason, who knows. maybe i’ll even overlook that little episode with the forged handwriting.”

“ `I was trying,` ” the anomaly wrote, “ `to give you some choice, for once.` ”

Somehow, Sans raised his eyebrows.

“oh. that actually sounds like a pretty good reason to me. what about you, alph?”

Alphys nodded with desperate agreeability.

“okay, seems we’ve reached common ground. for the sake of argument, let’s just call those previous few minutes a big misunderstanding and move on. what’s this choice you’re talking about?”

The anomaly took significant time putting together a response. Alphys felt pricks of moisture start to form on her hands again. It was hard to tell from Sans’ poker-faced reaction, but she’d jump into the Core if he was any less curious than she was at this strange proposition.

“ `I told you I tried to keep Frisk safe. I helped them break the barrier… but there’s more work to do. I thought that we could help each other. Do you know… Asgore and Toriel’s son?` ”

Sans stifled a laugh.

“wow. nothing like a good loaded question, huh? you never seem to run out of material. as for that one, though, the short answer’s ‘yes’. The long answer is ‘yeeeeeeeeeesssssssssssss’. yeah, i know about little asriel.  _ all  _ about him. why do you care?”

“ `Your brother isn’t the only one who didn’t get a happy ending.` ”

 

For a brief, heart-stopping instant, a reflected glare of cyan stabbed out of the anomaly’s dark monitor. Sans replied in a voice that probably lowered the temperature of all of Hotland.

“will you stop... bringing up…. _my_ _brother_? i know for a fact that you don’t have a clue about gaster, so do _not_ try to use him against me. _c a p i c h e_?”

The monitor did not take as long to recover from the outburst as before.

“ `I was afraid you’d say that. I thought maybe we might work together, to help them both. Even if I knew nothing, even if we never accomplished anything.`”

The screen paused to clear itself before continuing the text.

“ `But I understand if you can’t forgive me. Or even just trust me. So I wanted to offer you the choice you should have had from the beginning.` ”

From the darkened corner of the room, the silhouette of the DT Extractor emitted a barely audible beep. The long-lightless LED’s of it’s control panel began to glow once more as the monitor displayed yet another batch of text.

“ `The less detail I go into, the better for the mental well being of us all, but my interface with your world is... digital. I set the activation of the Determination Extractor to trigger an event on ` _ my end _ . ”

The screen scrolled once more.

“ `If you activate the machine, I will lose my interface. The data will be archived, and the program deleted. Probably permanently. Even if I were to re-create the link, it would likely be to a different reality than yours.` ”

 

Alphys’ eyes shot open. Sans looked stunned. If what the anomaly was saying was true, Alphys thought frantically, they were in a Mexican standoff where their opponent had just lowered their gun. If the creature on the other side of the monitor wanted to reset, it could have done so at any time- even while she and Sans had been chatting at Grillby’s. And that comment about Asriel… oh god. Speculation whipped her mind into a thunderstorm, and she feared that, if there’d been time to count before the thunderclaps, some of the lightning would turn out to have struck very close indeed. She stared at Sans’s implacable face, desperate to read his reaction.

The skeleton himself stood as though deep in thought, eyes closed, breathing serenely. Eventually, his bony eyelids slid ponderously open. He looked back at Alphys, and then the monitor again before letting loose a deep and blissful sigh.

 

“y’know, mr.anomaly,” he said, “i think i really had the wrong idea about you. sorry things got so heated.”

The next instant, after a frame of blackness, Sans was standing by the control panel, reaching for the button that would activate the Determination Extractor. He shrugged.

 

“no hard feelings, pal.”

  
  


*   *   *

 

Judging by the fact that she could still access the strings file for the True Labs’ voice logging system, nobody had pressed the button. 

Fumbling the mouse slightly, she closed the text file she’d been editing in the source directory and refreshed the strings. Then kept refreshing. The thought entered her head that even that one fanfic where Sans turned into a Lovecraftian toucan wasn’t quite as far-fetched as this drivel. 

  
  


*   *   *

 

“Wait!” screamed Alphys. 

 

Sans’ hand balled into a skinless fist just above the activation switch.

“i’m not going to wait, alphys.”

“Please!”

“you can’t change my mind here! for once in our lives, we can control our fate. we're definitely not passing up that chance.”

“Please just  _ wait _ !”

 

Even as Sans’ fingers extended toward the button, a strobing light erupted between him and the panel with a furious crackle. Once Sans’ eyes had recovered from the flash, he saw the the switch was cordoned off by a wall of writhing electricity.

“alphys... what are you doing?”

He sounded more bewildered than angry. Alphys herself looked as stunned as he did. She stared at her own outstretched hand with a hybrid expression of horror and amazement. 

“i don’t have much hp to spare, you know. care to explain why you just used magic on me?”

“He.. she… t-the anomaly d-d-doesn’t deserve this! You didn’t even c-consider!”

“it doesn’t matter that they deserve, alphys. they have too much power. even if they seem friendly now, what about in a week? in a year, after they’ve forgotten how much they used to care about this quaint little world that isn’t really theirs.”

Sans turned from the brilliant barrier to face her. Very slowly, he replaced his hand in his hoodie pocket.

“do you want to live like that? knowing that none of your memories will ever be safe? knowing that none of your choices might ever even matter?”

Alphys was beginning to tremble, but her magic didn’t show signs of wavering.

“It’s more than that. You s-said you knew about… Asriel. What did the anomaly mean about him n-needing help?”

“please, don’t ask about him, okay? he didn’t get what he deserved either. same deal with my bro- the anomaly hit that nail on the head at least. but if things had turned out differently, none of us would have made it past the barrier. sometimes, the world really just is that unfair. now let me  _ end this _ .”

“Sans, just tell me, p-please… is Asriel the flower?”

The lines under the skeleton’s eyes deepened. 

“look, alph, you and me might not exactly be birds of the same feather, but you're my friend. i don’t want to hurt you. i really,  _ really _ don’t. but i’ll promise you this: i’m not going to let this opportunity slip away, whatever it takes. i can’t afford to take it easy any more. so, if you wanna stay friends…  _ move. _ ”

He blinked, and when his eyes reopened, the blackness of his left socket was filled with pulsing light. He withdrew his left hand from it’s pocket, fingers haloed in the same cyan tinge, and levelled it at the quivering form before him.

 

Alphys felt some of the blood drain from her face. She’d never really considered that Sans could  _ do  _ magic, let alone fight with it, but this was certainly no joke. Whatever that glow was, it wasn’t anything like the enthusiastic bone attacks Papyrus had tossed at Frisk during their oft-recounted “battle”. This was… edgy. She found herself fighting back tears. As unsettling as the skeleton’s anger had been when directed at the anomaly, there was no replacement for the real deal. Far too many emotions at once were fighting for control of her body. She tried desperately, to think of something to say… anything to stop her own glimpsed opportunity from fading away. Finally, one thought came hurtling into her head hard enough to escape her mouth.

 

“What if it was Frisk?”

 

The terrible eye flickered out.

 

“...what?” 

 

Alphys let out one explosive sob- whether more from fear or relief she wasn’t sure- but caught her breath just as quickly. She didn’t dare let her meagre powers of speech fail now.

“You used to think Frisk was the anomaly, before the Barrier was broken. When did you decide they weren’t?”

“i... never knew for sure.”

“But you trusted them! Somehow, they must have convinced you they only wanted to help.”

 

This was it! Sans was clearly working through his own issues here, but beneath all his cynicism, and ruthless intellect, and meaningless smiles, Alphys knew there was a beating heart, if only in the strictly metaphorical sense. It could be glimpsed in the good-natured bickering he cultivated with his brother, or the so-bad-they're-bad jokes he only indulged in within earshot of Toriel. Most of all, when he was around Frisk...

 

“alphys,” Sans said, staring at the ground, “i know how you must be feeling here… and I think i’m feeling the same way.”

His gaze fell even farther downward.

“but trusting frisk was a mistake.”

 

Alphys felt her burgeoning hopes turn to ice and plummet somewhere into her gut.

“What? H-...how can you even  _ say  _ that?”

“i screwed up!” Sans shouted, throwing up his arms in exasperation.  “gollee, gee whiz, i sure am glad it turned out for the best! but what if it hadn’t? by letting that kid traipse through the underground unchecked, i was throwing everyone under a bus they didn’t even know was coming. i made a promise without thinking, let it get to my head… but here’s the bottom line: i’m not taking a chance like letting that kid live again!”

 

* (Ring… ring…)

 

Sans and Alphys, even as perspiration ran down their brows from the strain of magically attacking one-another, shared an awkward truce as the phone rang from Sans’ pocket.

“Are you gonna-”

“yeah, just hold on a sec…”

 

He dispelled the sinister glow around his left hand and snatched a flip phone out of his pocket. He flipped it open. Immediately, despite speaker-phone being disabled, the air was rent by the sawtooth whine of Papyrus’ voice.

“SANS, WHEN WILL YOU BE GETTING BACK FROM THE BATHROOM? FRISK AND I ARE IMPROVING TREMENDOUSLY WITHOUT ANYONE TO APPRECIATE OUR GREATNESS! AND ALL THE BASKETBALLS DEFLATED HALF AN HOUR AGO. FRISK ALSO WANTS TO EXPRESS THEIR DISSATISFACTION!”

There was a sound of plastic fumbling against bone. Sans hurriedly turned the volume up. A moment later, a soft voice crept through the speaker.

“Sans? I know you're not in the bathroom. You walked behind a telephone pole and never came out. Please come back soon, okay?”

“uh, yeah… sorry about that kiddo. i’ll be back in a sec. just helping alphys out with some… math.”

The resultant silence conveyed something along the lines of  “ -_- ”.

Frisk hung up. 

Sans wretchedly pocketed the phone.

Alphys, to the best of her ability, glared daggers.

 

“Sans, your brother is on the surface,  _ playing basketball _ ,  because you let that child live.”

The skeleton sagged. Somewhere in the universe, a sphere of orange rubber went  _ swish _ .

“you can quit it with the lightning, alph.”, he said. “you’re sweating more bullets than aaron in hotland. i won’t try anything.”

The crackling net vanished, plunging the room into relative darkness, and leaving Alphys to stumble exhaustedly against the wall.

 

“i guess neither of us are really meant for fighting, huh?”

Sans, too, leaned against the greenish wall, chest heaving slightly under the folds of blue cloth.

“let’s just talk instead. it’s easier. are you serious about trusting this thing to help us?”

“People need help, the anomaly wants to be that help. I think we owe it to them to try. Especially me…”

“yeah. not sure if i actually answered you before, but asriel is probably the flower.”

Alphys nodded forlornly.

“you really think there’s hope?” Sans continued. “both him and gaster are long gone. dead. soulless. i don’t even know where to start. most of all, i don’t want to get my hopes up again like i did before.”

Alphys, for once in her life, found words already on her lips.

“I don’t really know. But when Frisk was making their way through the Underground... they never gave up on anybody. Even when we were trying to kill them, or capture them, or rip out their soul, they never decided any of us weren’t worth helping. Not even when I betrayed them. They managed to break the  _ Barrier _ like that, somehow, so I guess they had the right idea. Maybe it’s our turn to… pay it forward.”

“tactical idiocy, huh? i guess it’s really just another way of saying ‘determination’ in the end anyway. and, uh, when you put it like that…”

Sans’ grin creaked wider.

“what the hell. why  _ not _ exploit the powers of an extradimensional god to resurrect dead monsters? sounds like a blast.”

“I’ve w-watched at least six surface TV shows where people do that so, so… I'm sure humans think it's pretty n-normal…?”

Sans have her a piercing look.

“no. i don't think they do. which is why it’s a good thing we're both monsters.”

 

He held out a metacarpal hand. Alphys grasped it, and the following handshake was even sweatier than before. Neither of them particularly cared. Once this ritual was completed, Sans whirled around and knocked sharply at the monitor three times.

“hey, you. after i get back from basketball, we’ve got some serious cud to chew. just don’t go fiddling with the timeline and never use my brother’s handwriting again, and you won’t have a b-”

Sans cleared his throat.

“and i won’t push that big, tempting activation stitch over there, okay?”

The monitor faded in one last, dumbfounded “`k`”.

“all’s well then. see ya alph.”

 

The universe blinked, and he was gone.

 

Alphys was left alone underground with a deity from an alternate reality.

A minute of silence passed.

Finally, she made the only conversation she could under the circumstances.

 

“So...um… you like anime?”

  
What appeared in answer were the three most beautiful letters Alphys would ever read.


	4. Epilogue

Dr. Wingding Gaster floated pensively in the Void Beyond Space. Six centuries passed, but he didn’t mind because it was also the Void Beyond Time. During an interval he felt was temporally appropriate, he had a thought. The thought was “ _ Is that really what Jerry’s Theme sounds like?”. _

Once this quandary had been given due consideration, he had a second thought. This thought, after dispersing and re-encoding around a passing embryonic universe, explored in depth the nature of sapient consciousness in a deterministic multiverse. In a plane where everything would happen, and yet only one thing could ever happened to anyone, the Doctor mused, perhaps it was only natural to concern one's self more with the infinity of events that did  _ not  _ take place within one’s sphere of being rather than with one’s own invariably allotted course. Maybe he, who each instant looked upon indefinite realities holding for him far kinder fates, was not unique in that regard.

The thought brought with it a poignant tang of melancholy. He savoured it, until his brilliant mind birthed a third, conclusive rumination. It was the kind of thought only accessible through the insight granted by pan-dimensional extrapolation. The ghost of a smile crept across his lips. 

“ _ At least I’m not one of those saps drawn in a goddamn turtleneck sweater.” _

  
Doctor Gaster laughed into the void, and stayed determined.

**Notes for the Chapter:**

> Considering the date of publication, it's hard to believe anyone actually reads these things any more, but if you've gotten this far I guess I can assume you do. In that case, thank you so much for reading! Please feel free to lambast me in the comments- it's how I sustain my life energy.
> 
> Also, shout out to a fellow called CourierNew who, despite never having spoken to me and not knowing I exist, taught me the valuable lesson that writing fan fiction doesn't automatically make you an antisocial degenerate. If you haven't already seen his/her/it's stuff, I'd question your judgement in spending half an hour reading my crap first. Anything good I managed to write here will probably turn out to be stolen from One by One anyway.


End file.
